So driving up here, I decided to tune into channel 19 and listen to truck drivers. Had lots of fun and even got one truck to let me draft off of him for a while. I've had my CB for a while now and I can get it to work, but I have no idea what each of the knobs do. I just turn this one a little and turn that one until it works for me. Can anyone tell me what each does and how I need to fine tune one of these things? What do I look for? or listen for? Is a power amp necessary?